Growth was more rapid among grass carp, Ctenopharyngodon idella Val., fed on cabbage, Brassica spp., than among those fed on kikuyu grass, Pennisetum spp. – despite the lower protein content of cabbage (11,9% vs 20,3%). The relative condition factor of fish fed on cabbage was also better. Proximate analysis was carried out and digestibility coefficients were obtained for the protein, fibre, ash and fat contents of both feeds. Cabbage was better digested and more efficiently utilized than grass with a feed conversion ratio of 3,3 compared to 9,7 for grass. Cabbage is a superior feed compared to grass for raising grass carp and a suitable low-cost alternative to commercial preparations.